RDNS

[Matt Kettler]

Darryl DeLao wrote:
> Is there a way to turn on RDNS in Mailscanner, or is this done in
> Sendmail?  If so, how is it done?  Basically, if an email comes in and
> the originating domain can not be resolved, I do not want to accept the
> email in the system.

Well, MailScanner can't ever prevent any email from being accepted. MailScanner
acts on the queue files, so by the time MS sees it, it's long since been accepted.


However, the feature you want is a standard sendmail feature. Look up the
"accept_unresolvable_domains" feature, and disable it.

If you're using m4 to build your sendmail.cf (highly recommended unless you're a
sendmail master)

edit /etc/mail/sendmail.mc

add a "dnl" to the start of the feature line, line this:

dnl FEATURE(`accept_unresolvable_domains')dnl

rebuild your sendmail.cf by running make in the /etc/mail directory

restart your MailScanner service to restart the sendmail's.